IBM 603 electronic multiplier

IBM 603 electronic multiplier

Announced on September 27, 1946, the IBM 603
Electronic Multiplier was the first electronic
calculator ever placed into production. It consisted
of two boxes: the Type 603 calculating unit (right
foreground) and Type 520 punch-read unit (left
background). This machine provided multiplication
speeds several magnitudes higher than earlier
electromechanical devices. In fact, computing
speeds were so much faster that multiplication
could be performed without the necessity of interrupting
card feeding.

All multiplication was performed
by the electronic tubes clearly visible here in
the 603 calculating unit. The factors read by
the 520 punch-read unit were transferred over
a cable to electronic counters in the 603. A control
panel on the 520 made it possible to wire the
machine for different multiplying and checking
operations. Calculation was performed almost simultaneously,
with the result transferred back to the 520 in
time to punch the answer in the same card. The
operation was continuous, with a card being read,
calculated and punched each cycle. The 603 had
a maximum reading and punching speed of 6,000
cards an hour, and it could multiply a six-digit
multiplicand and a six-digit multiplier for a
12-digit product.

One hundred 603s were manufactured, one of which has been preserved in the IBM Collection of Historical Computing Devices begun by Thomas J. Watson, Sr., in the 1930s. (VV2193)